The quality of farm systems is always in flux, whether because of acquisitions, graduations, or the overall ebb and flow of the prospects themselves. As such, ranking these prospects - as well as the farm systems they populate - is often a generalization based on opinions.
It can often be difficult to reach an industry consensus, as it pertains to player valuation While the top tiers of prospects are usually widely recognized from outlet to outlet, it often gets a bit cloudier as the lists go on. In some cases, certain prospects will appear highly on some lists, while being completely left off others.